How do you tell if an equation has no solution?

Question

anonymous · Answer

what kind of equation

turingtest · Answer

If it leads to an untrue statement
example:
3x=5x
$$3\neq5$$Not possible, so
3x=5x
has no solution

anonymous · Answer

graph the function and see if it hits the x axis ... if it does ... it has a real solution

anonymous · Answer

all equations have solutions  ... they may not be real though!!

anonymous · Answer

3x=5x has the solution x = 0

anonymous · Answer

3(0)=5(0)

turingtest · Answer

true, sorry I got lazy and tried to come up with an example without using a system of equations
real example:
x+y=0
x+y=1
has no solution because it leads to
0=1

anonymous · Answer

this is a system of equations .... the person just asked if an equation had a solution

turingtest · Answer

right, so I guess the answer is as you said, they all have solutions as long as it is one equation with one variable, they just may not be real.

anonymous · Answer

like does log(x) = 10 have a solution

turingtest · Answer

or 
log(x)=0
has an undefined solution, I'm not sure if that counts.

anonymous · Answer

yes but the range of the logarithmic function must be respected so the equation itself is invalid??

turingtest · Answer

Very good question...

anonymous · Answer

ah enuf of this ...lol

turingtest · Answer

Look for JamesJ or Zarkon to clear that kind of thing up.